Chris Willman Music Writer“We Love NYC: The Homecoming Concert,” the Clive Davis-programmed concert in Central Park, was called off just past its halfway point Saturday due to lightning strikes occurring within a 10-mile radius of the Great Lawn.Barry Manilow was mid-medley at 8:37 p.m. — with more than two hours left to go in the five-hour concert — when he was interrupted by an announcer saying: “Attention.